exploratory analysis based on the ICF framework
Joana Cruza,b
Alda Marquesb,c
Cristina Jácomeb
Raquel Gabrielb
Daniela Figueiredob,c
aDepartment of Health Sciences (SACS), University of Aveiro, Aveiro, Portugal bSchool of Health Sciences, University of Aveiro (ESSUA), Aveiro, Portugal
cUnidade de Investigação e Formação sobre Adultos e Idosos (UniFAI), Porto, Portugal
Corresponding author: Alda Marques, School of Health Sciences, University of Aveiro (ESSUA),
Campus Universitário de Santiago, Agras do Crasto, Edifício 30, 3810-193 Aveiro, Portugal.
Telephone: 00351 234 372 462; email: amarques@ua.pt
Running head: FUNCTIONAL BALANCE AND GLOBAL FUNCTIONING IN COPD
2
Abstract
Balance impairment is a common manifestation in older people with COPD and may contribute
to overall functional decline; however, the relationship between balance and global
functioning has not been studied. This study aimed to explore the global functioning of COPD
patients with and without functional balance impairment.
Functional balance was assessed with the Timed Up-and-Go (TUG) test and global functioning
with the Comprehensive ICF Core Set for Obstructive Pulmonary Diseases. Participants (n=134)
were divided in 2 groups according to their performance in TUG (with and without balance
impairment) and the ICF Core Set results were compared between groups.
Fifty-four (40.3%) participants had functional balance impairment. The groups presented a
similar extent of problems in several categories of the ICF components. However, participants
with balance impairment were more severely affected (p<0.05) in energy, pain, respiratory
system, weight maintenance, exercise tolerance, neuromusculoskeletal and movement-related
functions, and structure of head and neck. They also presented a significantly worse
performance in handling psychological demands and activities related to mobility, self-care,
domestic, community and social life, and a more negative perception of Environmental factors
related to products and technology of buildings for private use and social support services
(p<0.05).
Patients with functional balance impairment have more functional problems and are more
severely restricted in daily life than patients without compromised balance. Understanding the
relationship between balance control and global functioning will contribute to guide
3
Introduction
Chronic Obstructive Pulmonary Disease (COPD) is a highly prevalent disease worldwide and
one of the main leading causes of long-term disability [1]. The disease is characterized by a
progressive deterioration of pulmonary function associated with systemic features and
comorbidities which contribute greatly to functional performance decline [2]. Recent studies
have shown that balance impairment is also a common manifestation in patients with COPD
[3-10], particularly in older ages. These studies have found relationships between deficits in
balance control and disease severity [8], frequency of falls [10], reduced physical activity levels,
skeletal muscle weakness [7], dyspnea and fatigue [10]. While research has been focusing on
the mechanisms underlying balance control deficits and on the subsequent risk of falling, little
is known about the impact of balance impairments on daily functioning of patients with COPD.
Balance control, which includes maintaining postural stability during body movements [11], is
recognized as an integral component of daily (functional) activities [12]. Therefore, balance
impairments may reduce patients’ ability to live independently. Understanding the relationship
between balance impairment and global functioning is fundamental to guide rehabilitation
interventions aimed at maintaining functioning and minimizing disability.
The International Classification of Functioning, Disability and Health (ICF) is a multidimensional
framework developed by the World Health Organization [13] to assess human global
functioning. The ICF enables a comprehensive view of health states from a bio-psycho-social
perspective and provides an unified language for rehabilitation [13]. According to the ICF
framework, the problems associated with a health condition may concern body functions and
structures, performance of activities and participation in life situations, which may be further
facilitated or hindered by contextual (environmental or personal) factors. Therefore, this
framework may help professionals to detect changes in global functioning among people with
4 practice and research, ICF Core Sets for specific diseases have been developed [14]. ICF Core
Sets provide lists of categories that are relevant for specific health conditions and healthcare
contexts, thus reflecting the whole life experience of the person [15]. Specifically for COPD, the
application of the Comprehensive ICF Core Set for Obstructive Pulmonary Diseases (OPD) has
been found to describe impairments in patients’ global functioning [16]. However, the
question of whether these impairments differ in patients with and without compromised
balance remains unanswered. This study aimed to explore the global functioning of COPD
patients with and without functional balance impairment.
Methods
Design and ethics
A cross-sectional study was conducted after full approval from the Institutional Ethics
Committee involved.
Recruitment
Community-dwelling older adults with a clinical diagnosis of COPD (according to the ICD-10
code, J40-J44) were identified by the physicians of four primary care centers and one district
hospital, who ensured the fulfillment of eligibility criteria. Patients were included if they were:
i) 60 years old or over; ii) living in the community; iii) able to walk 3 meters with/without an
assistive device (but without the assistance of another person) and iv) able to follow simple
instructions. Patients were excluded if they had severe musculoskeletal, neurological or
cardiovascular disorders and severe auditory/visual impairments.
Patients were informed by their physicians about the study and asked about their willingness
5 schedule an appointment, from December 2010 to March 2012. Before data collection, more
information about the study was provided and the written informed consent obtained.
Data collection
The sample was first characterized. Participants were asked to complete a questionnaire with
socio-demographic information, smoking status, oxygen use and need for assistance to
perform the basic (mobility and personal care) and instrumental (e.g., domestic work,
medication management, transportation) activities of daily living. Height and weight were
collected to calculate the body mass index (BMI). Lung function was assessed according to
standardized guidelines [17] with a portable spirometer (MicroLab 3500, CareFusion, Kent,
UK). COPD severity was determined using the Global Initiative for Chronic Obstructive Lung
Disease (GOLD) criteria [18]: mild COPD (FEV1≥80% predicted), moderate COPD
(50%≤FEV1<80% predicted), severe COPD (30%≤FEV1<50% predicted) and very severe COPD
(FEV1<30% predicted).
Functional balance
Functional balance is defined as the ability to maintain equilibrium in dynamic situations
required for daily activities [11]. The Timed Up-and-Go (TUG) test [19] was used to assess
functional balance, as this is a simple and quick test used in clinical settings which incorporates
a series of tasks necessary for independent living [11]. Two TUG tests were performed and the
best performance was considered. To perform the test, participants were instructed to rise
from a chair, walk 3 meters as quickly and as safely as possible, turn around, return to the
chair and sit down [20]. Participants were encouraged to rest as needed between the tests.
Those who used an assistive device when walking were requested to use it during the tests.
6 Global functioning
Global functioning was assessed using the Comprehensive ICF Core Set for OPD, under which
COPD is included. This ICF Core Set has 71 ICF categories from all components of the ICF
checklist, including Body Functions (19 categories) and Structures (5 categories), Activities and
Participation (24 categories) and Environmental Factors (23 categories) [15]. Similarly to the
checklist, the ICF Core Set uses an alphanumeric coding system composed by a letter that
refers to the component (b, Body Functions; s, Body Structures; d, Activities and Participation;
e, Environmental Factors) and a numeric code starting with the chapter number (one digit),
followed by the second level (two digits) and the third level (one digit each), as in the example:
b2 Sensory functions and pain (chapter level)
b280 Sensation of pain (second level)
b2801 Pain in body part (third level)
This ICF Core Set includes 67 second level and 4 third level categories. For each category, a
qualifier was chosen to describe the extent of problems in the respective component
according to the following gradation: 0 (no problem), 1 (mild problem), 2 (moderate problem),
3 (severe problem) or 4 (complete problem). Additionally, 8 (not specified) was used when the
available information was not sufficient to quantify the severity of the problem and 9 (not
applicable) when a category was not applicable to that specific person [13]. In the
Environmental Factors component, a positive (+) or negative (-) sign was added to the numeric
qualifier to indicate whether the category was viewed by the participant as a facilitator or a
barrier, respectively. In the ICF, the domains of the Activities and Participation component can
be coded either using the performance qualifier, the capacity qualifier or both. The
performance qualifier describes what an individual does in his/her environment ("the lived
7 ability to execute a task/action in a standardized environment [13]. In this study only the
performance qualifier was coded to enable gathering the real day-to-day living experience of
patients with COPD.
There are still no specific assessment procedures for the ICF coding, therefore, the ICF Core Set
was completed by experienced researchers using a standardized protocol developed prior to
data collection that included information gathered throughout the interview, medical records
and physical exam. The physical exam included the assessment of BMI, heart and respiratory
rates, lung function and the observation of patient’s posture and performance during the TUG
test.
Data analysis
Participants were divided in two groups according to their performance in the TUG test:
patients with vs. without functional balance impairment. This was performed by comparing the
TUG score of each participant with the upper limit of 95% confidence interval (95%CI) of the
mean reference values of age-matched healthy peers [21]: score>9.0 seconds (60-69 years
old); score>10.2 seconds (70-79 years old) and score>12.7 seconds (80-99 years old). Patients
with a TUG score higher than the reference values were included in the group with balance
impairment.
Descriptive statistics were used to characterize the groups and describe global functioning
using the ICF Core Set. To enable between-group comparisons, the qualifiers 8 and 9 of the ICF
Core Set were recoded into a missing value and 0 (no problem), respectively.
Socio-demographic and clinical variables of both groups were compared using independent t-tests
for normally distributed data, Mann-Whitney U-tests for non-normally distributed data and
ordinal data, and Chi-square tests for categorical data. To assess differences between groups
8 A p<0.05 was considered for statistical significance. Effect sizes were calculated to measure the
strength of association between functional balance and ICF categories, using the formula
r=Z/√N [22], where r is the effect size, Z the test statistic of Mann-Whitney U-test and N the
total sample size. According to Cohen [23], r≥0.1 indicates a small, r≥0.3 a medium, and r≥0.5 a
large effect size. Analyzes were performed using PASW Statistics v18.0 for Windows (SPSS Inc.,
Chicago, Illinois).
Results
Participants
A total of 143 patients with COPD were contacted; however, 7 refused to participate as they
did not perceive the study as relevant and 2 did not complete the assessment. Therefore, 134
patients (85 males) with a mean age of 72.57±8.34 participated in the study. When comparing
patient’s TUG performance with the reference values [21], 54 participants (40.30%) were
included in the group with functional balance impairment and 80 (59.70%) in the group
without functional balance impairment (Table 1). The groups performed the TUG test in
14.94±6.58 and 8.22±1.59 seconds, respectively. In both groups, most patients were married,
retired and required assistance in at least one instrumental activity of daily living (p>0.05).
However, the percentage of participants dependent in at least one basic activity of daily living
was higher in the group with functional balance impairment (27.8% vs. 3.8%, p=0.001). This
group also presented a worse FEV1% predicted (p=0.013) and a higher BMI (p=0.005). The
groups included people at all COPD grades, although GOLD 4 was less prevalent.
(Insert table 1)
Global functioning of patients with and without balance impairment
9 Table 2 presents participants’ extent of problems in the Body Functions component. Emotional
functions (b152) and the respective subcategory (b1522), Exercise tolerance functions (b455)
and Sensations associated with cardiovascular and respiratory functions (b460) were found to
be at least moderately impaired in 50% of the participants from both groups (i.e., medians≥2).
Participants with functional balance impairment were significantly more affected than those
without balance impairment in the categories: Energy and drive functions (b130), Pain in body
part (b2801), Functions of the respiratory system (b440, b445), Weight maintenance functions
(b530), Exercise tolerance functions (b455) and in Sensations associated with cardiovascular
and respiratory functions (b460), and in all categories related to Neuromusculoskeletal and
movement-related functions (Chapter b7). A large effect size was found for Muscle power
(r=0.60) and Endurance functions (r=0.57) and a marginal medium effect size for Energy and
drive functions (r=0.29).
(Insert table 2)
Body Structures
The extent of problems in the Body Structures component is presented in Table 3. The groups
presented similar problems, with the exception of the Structure of head and neck region (s710)
which was worse in participants with functional balance impairment (p=0.016; r=0.21). The
structure most severely impaired in both groups was the Structure of the respiratory system
(s430, p=0.249), as presented in Table 3.
(Insert table 3)
Activities and Participation
Table 4 describes the extent of participants’ activity limitations and participation restrictions.
10 the groups, significant differences were observed in 15 categories (62.5%) of the Activity and
Participation component. Participants with functional balance impairment were more
restricted (p<0.05) in almost all categories of the Chapter d4 Mobility. Within this Chapter, the
effect size was moderate to large in the categories Changing basic body position (r=0.56),
Lifting and carrying objects (r=0.38), Walking (r=0.56) and Using transportation (r=0.39).
Other categories significantly affected in this group were Handling stress and other
psychological demands (d240) and categories related to the Chapters d5 Self-care (d510,
d540), d6 Domestic life (d650, d660) and d9 Community, social and civic life (d910, d920).
Nevertheless, a medium effect size was only observed for the categories related to Self-care
(Table 4).
(Insert table 4)
Environmental Factors
Within the Environmental Factors component, the categories Products or substances for
personal consumption (e110), Products and technology for personal use in daily living (e115),
Immediate family (e310), Health Professionals (e355) and the attitude of both family members
(e410) and health professionals (e450) were the most important facilitators for both groups
(Table 5). The most important barriers were related to Climate (e225) and Air quality (e260).
The categories Design, construction and building products and technology of buildings for
private use (e155) and General social support services, systems and policies aimed at providing
support to patients requiring assistance in daily activities (e575) were significantly different
between groups, with the participants with functional balance impairment perceiving them
more often as a barrier or a non-facilitator (Table 5). Nevertheless, the association between
functional balance and these categories was small (r=-0.20 and r=-0.22 for e155 and e575,
11 (Insert table 5)
Discussion
This exploratory study showed that, when compared to aged-matched healthy peers, 40.3% of
participants with COPD presented functional balance impairment. This group had more
functional problems and was more severely restricted in daily life than those without balance
impairment.
Body Functions
Both groups presented problems in Emotional functions (e.g., anxiety), Exercise tolerance
functions (e.g., fatigue) and in Sensations associated with cardiovascular and respiratory
functions (e.g., dyspnea). These functions are known to be often compromised in patients with
COPD [16]. However, this study found that, in the group with compromised functional balance,
the Functions of the respiratory system, Exercise tolerance functions and the Sensations
associated with cardiovascular and respiratory functions were more severely affected. These
results confirm the findings from previous research where disease-related factors, such as the
degree of airflow obstruction [8], hypoxemia, dyspnea and fatigue [10], were related to
balance impairments and falls in patients with COPD.
Patients with functional balance impairment also presented more severe problems in Energy
and drive functions, i.e., general mental functions that cause the individual to move towards
satisfying specific needs and general goals in a persistent way [13]. The concept of motivation
is of great relevance for older adults because it is one of the major factors associated to
functional limitations [24, 25]. In a previous study, patients with COPD had worse levels of
motivation to start an activity (p<0.001) when compared to healthy people [26]; however, the
12 investigate the association between these two variables and explore the underlying
mechanisms of this association.
In the present study, most patients were above the normal weight values (mean BMI
28.46±4.27 Kg/m2 and 26.52±3.55 Kg/m2 in patients with and without balance impairment,
respectively), reflecting the increasingly recognized relationship between COPD and obesity
[27, 28]. Nevertheless, patients with functional balance impairment had a significantly higher
BMI. Though increased body weight has been positively associated with impaired balance [29]
and higher prevalence of falls [30], the relationship between obesity and balance control in
COPD is yet to be determined.
The category Pain in a body part was also rated as more severe in patients with compromised
balance. Lihavainen et al. [31], exploring the relationship between musculoskeletal pain and
balance impairments in community-dwelling older adults, found that those with moderate to
severe musculoskeletal pain had more than twice the risk (Odds Ratio=2.33, 95%CI=1.44-3.76)
of having balance impairments when compared to those without pain. Possible mechanisms
were described, such as peripheral neuropathy with loss of sensation in the feet or altered
proprioceptive feedback from a painful site [31]. In this study, the location of pain was not
possible to determine due to the limited information obtained with the category Pain in body
part. Future studies should explore the role of body pain and its location on balance
dysfunctions in patients with COPD.
Neuromusculoskeletal and movement-related functions were significantly worse in patients
with functional balance impairment, particularly Muscle power (r=0.60) and Muscle endurance
(r=0.57) functions. Numerous clinical trials have found that muscle endurance is compromised
in these patients [32-34]; reduced muscle endurance reflects increased muscle fatigue [32],
which in turn has been associated with impaired postural control [35]. In COPD, one study
six-13 minute walking test) was one of the disease-related factors associated with balance
impairments [10], supporting the findings from the present study. It is also known that muscle
power (the product of force and velocity of muscle contraction) declines with age [36] and
appears to be more closely related to postural control [37] and functional performance [38,
39] than total muscle strength. In patients with COPD, balance impairments have been
associated with lower limb muscle strength (p<0.05) [7]. Although muscle power has not been
investigated in this population [40], it is unlikely that patients with COPD, with compromised
muscle strength [7], could have normal values of muscle power. This needs further
clarification.
Body structures
As expected from previous research [41], the respiratory system was the most severely
impaired structure in both groups. In contrast, the Structure of head and neck region was
significantly worse in people with functional balance impairment. In other populations,
subjects presenting a more protruded head with extensive neck posture (a similar pattern was
observed in the current study) showed a significantly decreased ability to control posture and
mobility [42]. In COPD, there are no studies directly evaluating head and neck posture.
Nevertheless, this positional change is frequently observed in older people [43] and in people
with breathing difficulties [44], such as patients with COPD [45].
Activities and Participation
Moving around was the category more severely rated by both groups. This category has been
found to be relevant for patients with COPD [46], with stair climbing being one of the most
14 Handling stress and other psychological demands was significantly affected in the group with
compromised balance. This category involves carrying out simple or complex and coordinated
actions to manage the psychological demands (i.e., stress, distraction or crises) required to
carry out tasks that impose significant responsibilities [13]. It has been suggested that
psychological stress associated to task demands could lead to a reduction in balance ability in
older adults [48]. In COPD, this topic has not been investigated.
All categories of the Chapter d4 Mobility (except Driving and Driving human-powered
transportation) and the categories Washing oneself and Dressing were significantly more
restricted in the group with functional balance impairment, with most of them showing a
medium to large effect size. Previous studies [7, 8, 10] using different measures which are
linked to the categories of these ICF Chapters [49, 50] also found that these patients have a
worse performance than their healthy peers. In this study, patients were also severely
compromised in activities related to Caring for household objects and Assisting others, and in
their participation in Community life, Recreation and leisure. These findings suggest that the
domestic and community lives are restricted in patients with functional balance impairment,
which may increase dependence on others and social isolation. This warrants further
investigation.
Environmental Factors
Most of the categories were similarly rated as facilitators or barriers by both groups. Previous
studies support these results [16, 51]. However, the group with compromised balance
presented a worse perspective about the Design, construction and building products and
technology of buildings for private use, suggesting a lack of accessibility conditions for these
people in private buildings (e.g., commercial stores). Further studies are needed to understand
15 development of strategies to facilitate their access. Moreover, a number of patients with
functional balance impairment rated General social support services, systems and policies as a
barrier, unlike patients in the other group. This finding indicates that those patients may
require assistance in areas such as shopping, housework, self-care and care of others, which
are not commonly covered by the existing services, systems and policies.
Study limitations
This study has several limitations that need to be acknowledged. First, the groups had uneven
distributions of COPD grades, with GOLD 4 (very severe COPD) being the less prevalent. Future
studies using samples with a more equitable distribution of COPD grades, including patients
from different countries, would be valuable to understand if body functions and structures
impairments, activities limitations, participation restrictions and the environmental
barriers/facilitators are similar to those found in this study. Second, in the present study, the
TUG test was used to stratify patients with or without balance impairment. Although this test
has been extensively used in older people [52] and in patients with COPD [3, 5, 8] to assess
functional skills, TUG is a rather basic functional balance test that cannot determine which
balance control systems are impaired [11]. Future studies should use a more comprehensive
clinical balance test, such as the Berg Balance Scale [53] or the Balance Evaluation Systems
Test (BESTest) [54], to identify the underlying balance control systems that are affected and
determine their impact on patients’ global functioning. Third, the performance of the Activities
and Participation component was coded to enable gathering patients’ daily living experience.
However, the assessment of both capacity (i.e., ability to execute a task/action in a
standardized environment) and performance (i.e., what the patient does in his/her
16 on patients’ activities and participation in the community. Measuring the gap between these
qualifiers (sometimes referred to as patients’ functional reserve [55]) may, therefore, help
determining what can be done to the current environment to improve patients’ performance.
Fourth, data were cross-sectional in nature; thus, the findings cannot demonstrate a causal
relationship between variables. Longitudinal studies are needed on this topic. Finally, the
current Comprehensive ICF Core Set for OPD does not include specific categories that could be
relevant to assess in more depth the impact of balance impairment on global functioning,
specifically those related to balance control and risk of falling [56] (e.g., b260 Proprioceptive
function, b210 Seeing functions, b235 Vestibular functions). This should be considered in future
revisions of this ICF Core Set.
Conclusion
This is the first study exploring the global functioning of COPD patients with and without
functional balance impairment. Findings suggest that patients with compromised balance have
more functioning problems and are more severely restricted in daily life than those without
balance impairment. Understanding the relationship between balance control and global
functioning, as performed in this study, will contribute to guide interventions aimed at
17
Acknowledgments
The authors would like to acknowledge all institutions and patients involved for their
participation in this study. We are also very grateful to Ana Gonçalves, Carla Lucas and Sara
18
Declaration of Interest
This work was funded by Fundação para a Ciência e Tecnologia, Portugal (project ref.
19
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25
Table 1 – Socio-demographic and clinical characteristics of participants with and without functional balance impairment. Patients without functional balance impairment (n=80) Patients with functional balance impairment (n=54) p-value
Age (years), mean (SD) 71.79 (8.23) 73.74 (8.46) 0.185
Gender (male), n (%) 55 (68.8%) 30 (55.6%) 0.145 Living alone, n (%) 9 (11.2%) 11 (20.8%) 0.145 Marital status, n (%) Single 3 (3.8%) 0 0.088 Married/Living as a couple 62 (77.4%) 39 (72.2%) Separated/divorced 5 (6.2%) 1 (1.9%) Widowed 10 (12.5%) 14 (25.9%) Current occupation, n (%) Employed 7 (8.8%) 1 (1.9%) 0.150 Unemployed 2 (2.5%) 2 (3.8) Domestic work 3 (3.8%) 0 Retired 68 (85.5%) 51 (94.4%)
Dependency in at least one basic activity of
daily living, n (%) 3 (3.8%) 15 (27.8%) 0.001*
Dependency in at least one instrumental
activity of daily living, n (%) 49 (61.3%) 38 (77.6%) 0.081
FEV1% predicted, mean (SD) 68.40 (22.41) 58.00 (24.65) 0.013*
GOLD grade, n (%) GOLD 1 31 (38.8%) 14 (25.9%) 0.013* GOLD 2 33 (41.2%) 15 (27.8%) GOLD 3 13 (16.2%) 20 (37.0%) GOLD 4 3 (3.8%) 5 (9.3%) BMI (Kg/m2), mean (SD) 26.52 (3.55) 28.46 (4.27) 0.005* Smokers, n (%) 20 (25.0%) 2 (3.7%) 0.001* Oxygen use, n (%) 2 (2.5%) 8 (14.8%) 0.015*
26
SD, standard deviation; FEV1% predicted, percentage predicted of the forced expired volume in one
second; GOLD, Global Initiative for Chronic Obstructive Lung Disease; BMI, body mass index; *Significant atp<0.05.
27
Table 2 - Extent of problems in the Body functions component of participants with and without functional balance impairment.
ICF code ICF category Patients without
functional balance impairment (n=80) Patients with functional balance impairment (n=54) p-value Effect size (r)
b130 Energy and drive functions 0 [0-4] 1 [0-4] 0.001* 0.29
b134 Sleep functions 1 [0-4] 2 [0-4] 0.526 0.05
b152 Emotional functions 2 [0-4] 2 [0-4] 0.283 0.09
b1522 Range of emotion 2 [0-4] 2 [0-4] 0.334 0.08
b280 Sensation of pain 1 [0-3] 2 [0-4] 0.121 0.13
b2801 Pain in body part 1 [0-3] 2 [0-4] 0.009* 0.23
b310 Voice functions 0 [0-3] 0 [0-3] 0.177 -0.12
b410 Heart functions 1 [0-3] 1 [0-3] 0.354 0.08
b430 Haematological system functions 0 [0-4] 0 [0-3] 0.610 0.04
b435 Immunological system functions 0 [0-4] 0 [0-4] 0.799 0.02
b440 Respiration functions 1 [0-4] 1 [0-4] 0.011* 0.22
b445 Respiratory muscle functions 1 [0-4] 1 [0-4] 0.004* 0.25
b450 Additional respiratory functions 1 [0-3] 1 [0-4] 0.858 0.02
b455 Exercise tolerance functions 2 [0-4] 3 [0-4] 0.003* 0.26
b460 Sensations associated with
cardiovascular and respiratory functions
2 [0-4] 3 [0-4] 0.002* 0.27
b530 Weight maintenance functions 1 [0-2] 1 [0-3] 0.004* 0.25
28
b740 Muscle endurance functions 0 [0-1] 1 [0-3] 0.001* 0.57
b780 Sensations related to muscles and movement functions
0 [0-4] 1 [0-4] 0.042* 0.18
29
Table 3 - Extent of problems in the Body structures component of participants with and without functional balance impairment.
ICF code ICF category Patients with
functional balance impairment (n=54) Patients without functional balance impairment (n=80) p-value Effect size (r)
s410 Structure of cardiovascular system 1 [0-4] 1 [0-4] 0.591 0.05
s430 Structure of respiratory system 2 [0-4] 2 [0-4] 0.249 0.10
s710 Structure of head and neck region 2 [0-2] 0 [0-3] 0.016* 0.21
s720 Structure of shoulder region 0 [0-2] 0 [0-3] 0.053 0.17
s760 Structure of trunk 0 [0-3] 0 [0-3] 0.813 -0.02
30
Table 4 - Extent of problems in the Activities and Participation component of participants with and without functional balance impairment.
ICF code ICF category Patients without
functional balance impairment (n=80) Patients with functional balance impairment (n=54) p-value Effect size (r)
d230 Carrying out daily routine 1 [0-4] 1 [0-4] 0.073 0.15
d240 Handling stress and other psychological demands
0 [0-4] 1 [0-4] 0.007* 0.23
d330 Speaking 0 [0-3] 0 [0-3] 0.686 0.03
d410 Changing basic body position 0 [0-1] 1 [0-3] 0.001* 0.56
d430 Lifting and carrying objects 0 [0-3] 1 [0-4] 0.001* 0.38
d450 Walking 0 [0-2] 1 [0-4] 0.001* 0.56
d455 Moving around 2 [0-4] 3 [0-4] 0.004* 0.25
d460 Moving around in different locations 1 [0-4] 2 [0-4] 0.026* 0.19
d465 Moving around using equipment 0 [0-4] 0 [0-4] 0.001* 0.28
d470 Using transportation 0 [0-4] 2 [0-4] 0.001* 0.39
d475 Driving 0 [0-2] 0 [0-4] 0.336 0.08
d4750 Driving human-powered transportation 0 [0-4] 0 [0-4] 0.140 0.13
d510 Washing oneself 0 [0-4] 1 [0-4] 0.001* 0.31
d540 Dressing 0 [0-4] 2 [0-4] 0.001* 0.34
d570 Looking after one’s health 0 [0-4] 0 [0-3] 0.837 -0.02
31
d640 Doing housework 1 [0-4] 2 [0-4] 0.121 0.13
d650 Caring for household objects 1 [0-4] 2 [0-4] 0.018* 0.20
d660 Assisting others 0 [0-4] 0 [0-4] 0.008* 0.23
d770 Intimate relationships 0 [0-4] 0 [0-4] 0.884 0.01
d845 Acquiring, keeping and terminating a job
0 [0-4] 0 [0-4] 0.160 -0.12
d850 Remunerative employment 0 [0-4] 0 [0-0] 0.026* -0.19
d910 Community life 0 [0-4] 1 [0-4] 0.042* 0.18
d920 Recreation and leisure 1 [0-4] 2 [0-4] 0.001* 0.28
32
Table 5 - Extent of problems in the Environmental Factors component of participants with and without functional balance impairment.
ICF code ICF category Patients without
functional balance impairment (n=80) Patients with functional balance impairment (n=54) p-value Effect size (r)
e110 Products or substances for personal consumption
4 [0-4] 4 [0-4] 0.682 0.04
e115 Products and technology for personal use in daily living
3 [0-4] 3 [0-4] 0.466 0.06
e120 Products and technology for personal indoor and outdoor mobility and transportation
0 [0-4] 0 [-4-4] 0.996 0.00
e150 Design, construction and building products and technology of buildings for public use
0 [-2-4] 0 [-4-2] 0.060 -0.16
e155 Design, construction and building products and technology of buildings for private use
0 [-2-4] 0 [-4-2] 0.018* -0.20
e225 Climate -3 [-4-1] -2 [-4-3] 0.145 0.13
e245 Time-related changes -1 [-4-0] -1 [-4-1] 0.857 0.02
e2450 Day/night cycles -1 [-4-0] -1 [-4-2] 0.916 0.01
e260 Air quality -2 [-4-3] -3 [-4-3] 0.818 -0.02
e310 Immediate family 4 [-4-4] 3 [-4-4] 0.119 -0.13
e320 Friends 0 [0-4] 0 [-1-4] 0.080 -0.15
e340 Personal care providers and personal assistants
1 [-4-4] 1 [0-4] 0.759 -0.03
33
e410 Individual attitudes of immediate family members
2 [-3-4] 2 [-2-4] 0.751 0.03
e420 Individual attitudes of friends 0 [0-4] 0 [0-4] 0.361 -0.08
e450 Individual attitudes of health professionals
3 [0-4] 3 [-2-4] 0.679 0.04
e460 Societal attitudes 0 [-1-2] 0 [-3-1] 0.060 -0.16
e540 Transportation services, systems and policies
0 [-2-4] 0 [-2-4] 0.450 0.07
e555 Associations and organizational services, systems and policies
0 [0-4] 0 [-1-2] 0.633 -0.04
e575 General social support services, systems and policies
0 [0-2] 0 [-4-0] 0.011* -0.22
e580 Education and training services, systems and policies
1 [-3-4] 2 [-4-4] 0.366 0.08
e585 Labour and employment services,
systems and policies
0 0 [0-2] 0.224 0.11
e590 Labour and employment services,
systems and policies
0 [0-3] 0 [0-2] 0.787 0.02
